50 watts out only SSB,450D?

All of a sudden my old Yaesu 450D will only TX 50 Watts out in SSB per the radio and palstar meters..CW,FM both show 100 watts out..Tuning has changed a bit also..Receive is fine...I have not changed a thing in menus..I did a full reset,no go...What could cause this,Bob/KF7WMM

Normally unless you use an oscilloscope or a very good "true PEP" (powered) wattmeter, SSB output should read about 30% of CW carrier power, or 30W on voice peaks as you're speaking. But a very good PEP meter (which requires DC power to operate) could show 100W PEP.

If you can get an SSB rig to show "full power" on SSB with a regular wattmeter, something's wrong and would normally mean a lot of distortion.

Thanks for the reply,until a few hours ago,both meters showed the same,90 to 100 watts out on SSB transmit..If I key down on FM it shows almost 100 out,same on CW..I have a practice key,on SSB key down is only 50 watts,what the heck,Bob

Thanks for the reply,until a few hours ago,both meters showed the same,90 to 100 watts out on SSB transmit..If I key down on FM it shows almost 100 out,same on CW..I have a practice key,on SSB key down is only 50 watts,what the heck,Bob

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It should have never shown 100W on SSB. What you're seeing "now" is actually normal; to indicate 100W on SSB is not normal, I suspect something was wrong either with the readings or the rig was being very overmodulated.

It should have never shown 100W on SSB. What you're seeing "now" is actually normal; to indicate 100W on SSB is not normal, I suspect something was wrong either with the readings or the rig was being very overmodulated.

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got me wondering now... my 450D if u toss a tone to the mic jack.. will show 100 on ssb on radio and xtern meter. on phone voice used. shows peakin 75ish..

wonder what SWRs are showing.. tuner in use when doesnt need to be? tuner not used ? antenna ? coax?
i know my 450 will kick it back if swr goes high.

I was actually going to suggest the same process. You can download an app called "Soundcheck" for your iPhone (I'm sure there are similar apps for Android devices). The app will let you play a constant tone. I use 800Hz as a test frequency. Anyway, activate the test tone and hold the phone by your mic when transmitting ("toss a tone"). My 450 shows 100 watts on SSB when using the 800Hz tone, provided the SWR is under 1.5:1.

If the SWR rises above about 2.0:1, the radio will start to reduce power in order to protect the finals ("kick it back").

Hope this helps. As far as the solution to your problem, I don't know.....